Glaciated and mixed phase ice accretion modeling using ONERA 2D icing suite

Abstract

In the framework of HAIC European project, a capability for modeling glaciated and mixed-phase ice accretion has been added to IGLOO2D, the new ONERA 2D icing suite. A first set of models has been introduced for taking into account physical phenomena which are generally not considered for classical icing conditions: particle shape influence on the drag force, heat exchange between air and particles, melting and evaporation phenomena, complex particle interactions with dry and wetted walls, liquid film dynamics, influence of ice crystals on energy balance ... To assess this new capability, test cases have been performed for mixed-phase ice accretion using results from the NASA-NRC experimental database 3,4 . Nomenclature d : Particle equivalent diameter (sphere of same volume) r : Particle equivalent radius m : Particle mass T : Temperature Tf : Melting / Freezing temperature Tp,m : Mean particle temperature Tp,s : Mean surface particle temperature y, : Mass fraction h : Enthalpy per unit mass Lv : Latent heat of vaporization Lm : Latent heat of melting FD : Drag force v : Velocity w : Relative velocity between air and particle g : Gravity acceleration ρ : Density μ : Dynamic Viscosity c : Specific heat capacity k : Heat conductivity D : Diffusivity h t : Heat exchange coefficient : Ice surface energy C D : Usual particle drag coefficient C d : Normalized particle drag coefficient (based on the sphere of same volume) : Convective heat flux Re : Reynolds Number Nu : Nusselt Number Sh : Sherwood number 1 Senior Scientist, Aerodynamics and Energetic Modeling Dept., BP 4025 2 avenue Ed. Belin, Toulouse, F. 2 Research engineer, PhD, Aerodynamics and Energetic Modeling Dept., BP 4025 2 avenue Ed. Belin, Toulouse, F. 3 PhD student, Aerodynamics and Energetic Modeling Dept., BP 4025 2 avenue Ed. Belin, Toulouse, F. . 2 American Institute of Aeronautics and Astronautics Sc : Schmidt number Pr : Prandtl number : impact dimensionless parameter e : Spheroid eccentricity E : Particle aspect ratio : Particle sphericity : Particle crosswise sphericity : Particle surface area : Particle crosswise surface area Subscripts a : air c : crystals d : droplets p : particle w : water i : ice s : particle surface or solid phase l : liquid phase v : vapor phase ∞: relative free stream conditions 0 : initial condition imp: impacting droplets or crystals